22, e Lee: A Disease of Orange Fruits 611 



young, actively growing Tahiti lime twigs ; twenty young, actively 

 growing leaves of Unshiu orange trees ; thirty old senile leaves 

 of the same species; and twelve twigs of a mandarin orange 

 tree. The results of the last inoculations were entirely negative 

 in each case, while controls on Batangas mandarin orange fruits 

 were positive. 



Table 3.— Showing results of inoculation* with etnOrol puncture* and punc- 

 tures with infusion of spores of Gloeosporium foliieohim on fruits under 

 orchard conditions. 



The inoculations were repeated with similar results; all the 

 inoculations on twigs remained negative, while on mandarin 

 orange fruits positive results were obtained. Apparently, if, as 

 described by Nishida, this fungus causes a wither tip disease of 

 young, actively growing twigs, a peculiar set of environmental 

 conditions is necessary or a weakened host plant is essential. In 

 the cases of Colletotrichum gloeosporioides Penzig, such is the 

 case according to R. E. Smith and E. H. Smith, (9) E. 0. Essig,(4) 

 and R. E. Clausen. (l) , 



The results would seem to warrant the retention for the present 

 at least of Nishida's species, Gloeosporium folucolum, since it is 

 particularly pathogenic to mature fruits of the Unshiu and man- 

 darin oranges, Citrus nobilis; while of the closely related specie 

 it is distinguished from Colletotrichum gloeosporioides by its 

 absence of pathogenicity on mature fruits of lemon and sweet 

 orange, C. limonia and C. sinensis, and from Gloeosporium hm et- 

 ticolum by being nonpathogenic to young fruit and twig tissues 

 of the lime, C. aurantifoha. 



The pressure of other work prevents a ™" ^P ,ete ^* 

 of these three fungi, morphologically and in culture as well as 

 physiologically. 



